Chapter 5.7, Problem 4STP

For Exercises $1-5,$ choose the correct letter.

A city had a population of 150,000 people in 1990. The population growth of the city is represented by the equation $p=5t+150$

where $p$ is the population in thousands and $t$ is the time in years since 1990. In what year will the population have doubled?

F. 1993

G. 2000

H. 2020

I. 2030

To determine

To find: the year that the population becomes doubled.

Answer to Problem 4STP

Option $H)2020$is correct.

Explanation of Solution

Given information:

The population growth is represented as $p=5t+150$

Here, p is the population in thousands;

t is the time in years since $1990.$

population growth is represented as $p=5t+150$

The city population is $150,000$ people in $1990.$

Calculation:

Consider $p=5t+150$

If population doubles,

  $\begin{array}{l}2p=5t+150\\ 2(150)=5t+150\\ 300-150=5t\\ t=\frac{150}{5}\\ t=30\end{array}$

So, the year is $1990+30=2020$

Hence,

Option H is correct.